Conventionally, with radar apparatuses, pulse compression is performed on reception signals to improve a resolution in a distance direction (JP2008-096337A). The reception signals include a signal (interference signal) which is caused by an influence of, for example, an electromagnetic wave transmitted to a ship equipped with the radar apparatus from another ship and does not continue in an azimuth direction.
Therefore, processing of removing an interference component from the reception signals (e.g., processing of replacing the level of a sudden high level signal to zero).
However, depending on the contents of the interference removing processing, an appropriate echo cannot be displayed. For example, as described above, when the level of the reception signal determined to be the interference component is replaced to zero, only the part of the reception signal becomes zero. Therefore, an image with a partial lack of echo image is displayed, and results in degrading a display quality as the radar apparatus.